Introduction

There are three types of amplifiers known to be used within an over-the-air TV system. These are:

1.) Distribution Amplifier & Powered Splitter
2.) Preamplfier or preamp

This page, very briefly, discusses the distribution amplifier and the powered splitter. This page discusses the preamp in much more detail. This is due to the fact distribution amplifiers and/or powered splitters are rarely used today. For more information on the most effective way to connect a multiple TVs to one TV antenna, read the article titled "The Best Way to Connect Multiple TVs to One TV Antenna" .

Distribution Amplifier and Powered Splitter

A distribution amplifier is a term often used loosely within over-the-air television. Sometimes a distribution amplifier is referred as a powered splitter. They are essentially the same thing. A distribution amplifier is used when multiple TVs are connected to one TV antenna. Connecting multiple TV tuners to one TV antenna requires the TV signal to be split multiple times. This causes the signal to be weakened considerably. If long coax cables are used, to each TV tuner, the signal will be weakend by the cables. A distribution amplifier is used to amplify the TV signal to overcome the signal weakening caused by splitting and long coax cables. A distribution amplifier is commonly used in motels, apartment complexes, and large houses. One TV antenna may be used to serve many different units. As a result, the TV signal needs to be split many times and long coax cables are needed to run from the distribution amplifier to each unit. A distribution amplifier is used to amplify the TV signal in these cases.

Unlike a preamplifier, a distribution amplifier is NOT placed near the TV antenna. Instead, a distribution amplifier is placed in between the coax cable, that comes from the TV antenna, and coax cables that run to each TV tuner. Unlike a preamplifier, a distribution amplifier does NOT use the coax cable to receive power. Instead, distribution amplifiers usually have a separate power input connector and a separate power cord that is connected to the power adapter. A preamplifier uses the coax cable to deliver power from the power adapter to the preamp. This is so you don't have to run a separate power cord to the preamp. A preamp's power adapter is located indoors and it hooks to the same coax cable that is hooked to the output of the preamp. Using the coax cable to deliver both the TV signal and power, allows a preamp to be located outside whereas a distribution amplifier is located indoors.

A distribution amplifier relies on a good and relatively strong input signal. As mentioned above, the sole purpose of a distribution amplifier is to amplify the signal as a result of physically splitting the signal multiple times and sending the signal down several long runs of coax cable. A good preamp does not need such a strong input signal to be effective. As long as there IS a signal, a good preamp can amplify it. A preamp usually has only one input and one output. A preamp is always located near the antenna. The output of the antenna is connected to the input of the preamp. The preamp is then connected to the coax cable that runs to the TV tuner.

It is not recommended to physically split an over-the-air TV signal. Refer to the article titled The Best Way to Connect Multiple TV's to One TV Antenna.

Preamplifiers (preamps)

A TV antenna preamplifer or "preamp" is sometimes referred as a "booster". Outdoor antennas usually require a very long coax cable in order to connect from the antenna to the TV tuner. A long coax cable weakens the TV signal before it reaches the TV Tuner. As a result, this long coax cable can cause the loss of TV channels and poor TV reception. The primary purpose, of an antenna preamp, is to amplify the TV signal before it is sent through the long coax cable. A preamp is an amplifier that contains only one input and one output. The preamp is always placed near the antenna. Even if the TV antenna is located outside, the preamp is placed outside near the antenna. The output, of the TV antenna, is connected to the input of the preamp. The output of the preamplifer is connected to the input of the TV tuner. It is common for the output of the preamp to use a very long coax cable to reach the TV tuner. Preamps are also used with short coax cables. This is done in an attempt to get more channels by amplifying weak TV broadcasts. Sometimes preamps can get more channels and sometimes not. The user should try using their TV system while using a good quality preamp and try without using a preamp.

Although preamps are placed near the antenna, the power adapter is placed at the other end of the coax cable, near the TV tuner. The power is sent through the coax cable, to the preamp. The coax cable that runs from the preamp to the TV tuner is used as the power cable. This is commonly done so you don't have to run a separate extension chord to power the preamp.

Since the coax cable is used to supply power to a preamp, it is essential that a good quality coax cable is used. Not all coax cable is the same. Using the wrong coax cable almost always results in preamp malfunction and poor TV reception. Many cheap coax cables contain a composite center conductor. This is type of cable will almost result in poor preamp performance and poor TV reception. A coax cable, that contains a solid copper center conductor, is always recommended. Refer to the page titled Coax Cable - What You Need to Know to choose the proper coax cable for your TV system.

Some TV antennas contain a built-in preamp. Before purchasing and installing an external preamp, be sure your TV antenna does not contain a built-in preamp. Using more than one amplifier, within your TV system, will result in very poor performance and you may loose channels. If you are using a distribution amplifier and/or using a powered splitter it is recommended that you disconnect ALL amplifiers and use only one preamplifier within your entire TV system. This is due to the fact amplifiers introduce noise into the signal. If there is more than one amplifier between the antenna and the TV tuner, the signal gets too noisy. This is a result of noise being added to the signal from each of the amplifiers. If you are physically splitting your signal, consider removing all of your splitters, remove any and all distribution amplifiers, and use one of the recommended preamps. If you need to split your TV signal to multiple TVs, use an external WIFI tuner instead of physically splitting the signal. For more information on the recommended method for splitting a TV signal to multiple TV's, without weakening the signal, read this article:The Best Way to Connect Multiple TV's to One TV Antenna.

Like TV antennas, there are many low-quality, offshore made preamps that contain hundreds of positive reviews. Purchasing a good quality preamp is essential for good TV reception and good overall TV system performance. For a list of good quality preamps, be sure to read the section titled Recommended TV Antenna Preamps

A distribution amplifier is used when a TV system physically splits the coax cable several times. The tv signal is physically split to multiple places, usually to multiple bedrooms. Every time the signal is split, a significant amount of TV signal loss occurs. A distribution amplifier is a splitter with an amplifier built-in. Unlike a preamp, a distribution amplifier is placed indoors. A distribution amplifies the signal in an effort to overcome signal loss resulting from splitting the TV signal multiple times. Although there are commercial reasons why a distribution amplifier should be used, it is not recommended to split a TV antenna signal within a single home or apartment. For information on the best way to hook up multiple TV's to one TV antenna visit the this article: The Best Way to Connect Multiple TV's to One TV Antenna.

How do I Know if I Should Use a Preamp?

Although the original intention of a preamp is to be used if you are using a long coax cable, preamps often increase the number of channels you can receive. Using a preamp, on short coax cable runs, can increase the number of channels you can receive. This is because preamps help in receiving the weak broadcast stations. Preamps can also decrease signal drop-outs even if you are using a short coax cable. In some cases, using a preamp can reduce the number of channels you receive. This is due to the fact the preamp might over amplify the TV signal. This will "overdrive" some TV tuners. There are some preamps, on the market, that have an adjustable gain. This allows the user to adjust the preamp's gain so the amplifier provides the right amount of signal boost without "overdriving" the TV tuner. There are also preamps that have "variable" gain. These preamps automatically adjust the signal gain so that the right amount of boost is always provided. Different people have different results when using a preamp. It is recommended to try a preamp and compare your results to not using a preamp. There are hundreds of low-quality, offshore made preamps. These preamps have hundreds or thousands of good reviews within major shopping websites. As a result, these low quality preamps will always appear within the first 10 to 20 pages of search results at major shopping websites. It is essential to use a good quality preamp if you would like the best possible results within your TV system. Be sure to read the section titled Recommended TV Antenna Preamps.

What You Need to Know Before Buying and Before Using a TV Antenna Preamp

Proper Location of the Preamp

As mentioned previously, the preamp should be located and hooked up near the antenna. The power supply is located on the other end of the coax cable, near the TV tuner. The power is sent through the coax cable up to the preamp. Not all coax cable is the same. It is essential that you use the correct coax cable when using a preamp. Read this page titled Coax Cable - What You Need to Know. For outdoor antennas, the preamp will be located outside. Preamps are electronic. Weather imposes a severe beating on preamps. As a result, the preamp is the number one reason why existing over-the-air TV systems experience sudden issues or stops working all together. When preamps experience issues or they stop working, no warning is given. No message is displayed on your screen. You simply loose all of your channels. With that said, it is critical that you use a good quality preamp from a reputable manufacturer. For this reason, it is always a good idea to have a spare preamp on hand.

Using More Than One Preamp

Some TV antennas have preamps built-in. If more than one preamp is used, a TV system will not function correctly. Amplifiers insert noise into the TV signal. When more than one preamp is used the TV signal will be over amplified and too much noise will be placed into the TV signal. The TV tuner will have trouble decoding the signal. Before buying a preamp, check your existing antenna and confirm that it does not already contain a built-in preamp. Televes is an good quality antenna manufacturer that has preamps built into their antennas.

Passive Pass-Through

Some TV antenna preamps have a featured called "Passive Pass-Through" or "Pass-Through". This feature allows the TV antenna signal to simply "pass-through" the preamp in the event that the preamp fails. When the preamp fails, unamplified signals will simply pass through the preamp and onto the TV tuner. When a preamp fails and it does not have a pass-through feature, the preamp does NOT allow any of the TV signal to reach your TV tuner. When a malfunction occurs, while using a preamp that does not have "pass-through", none of the TV channels are watchable. The TV system goes completely dead. This includes the inability to watch strong TV stations as well as the weak stations. When a malfunction occurs, while using a preamp that contains "pass-through", the end-user will notice their weaker TV stations are no longer watchable. However, the stronger stations will, most likely, still be viewable.

Built-In LTE Filter

Some TV antenna preamps have a built-in LTE filter. The LTE filter simply removes all cell tower signal interference from the TV signal stream. In almost every location, there will be dozens, if not, hundreds of cell towers between your TV antenna and the TV broadcast tower. Cell towers cause a lot of interference on broadcast TV signals. Cell tower interference is one of the most common reception problems people experience. As a result, it is recommended to always use a LTE filter on your over-the-air TV system. If the preamp does not contain a built in LTE filter, separate LTE filters can be purchased. A separate LTE filter always gets hooked-up between your TV antenna and the input to your preamp.Be sure to check and see if the preamp has a built-in LTE filter.

Recommended TV Antenna Preamplifiers (Preamps)

Recommended Preamplifiers (Preamps)

Preamp Manufacturer: Televes	Preamp Manufacturer: Antennas Direct	Preamp Manufacturer: Channel Master	Preamp Manufacturer: Winegard
Preamp Model: 560383	Preamp Model: Clearstream JUICE	Preamp Model: CM-7779HD	Preamp Model: Boost XT - LNA-200
Has Pass-Through: Yes	Has Pass-Through: No	Has Pass-Through: Yes	Has Pass-Through: No
Has built-in LTE Filter: Yes	Has built-in LTE Filter: No	Has built-in LTE Filter: Yes	Has built-in LTE Filter: No
Adjustable Gain Control: Yes	Adjustable Gain Control: No	Adjustable Gain Control: Yes	Adjustable Gain Control: No
Adjustable Gain Control Type: Automatic	Adjustable Gain Control Type: None	Adjustable Gain Control Type: Manual	Adjustable Gain Control Type: None
MSRP: $69.95	MSRP: $79.99	MSRP: $85.00	MSRP: $51.49